title: Passive sampling of selected pesticides in aquatic environment using polar organic chemical integrative samplers.
abstract: OBJECTIVE
  Polar chemical integrative samplers (POCIS) were examined for their sampling efficiency of 12 pesticides and one metabolite commonly detected in surface waters. Laboratory-based calibration experiments of POCISs were conducted. The determined passive sampling rates were applied for the monitoring of pesticides levels in Lake Amvrakia, Western Greece. Spot sampling was also performed for comparison purposes.
  
  
  METHODS
  Calibration experiments were performed on the basis of static renewal exposure of POCIS under stirred conditions for different time periods of up to 28 days. The analytical procedures were based on the coupling of POCIS and solid phase extraction by Oasis HLB cartridges with gas chromatography-mass spectrometry.
  
  
  RESULTS
  The recovery of the target pesticides from the POCIS was generally >79% with relative standard deviation (RSD) <16%. The calibration results revealed an integrative uptake of all pesticides for 28 days and the calculated sampling rates ranged from 0.025 to 0.388 L day(-1) with RSD <29%. Low nanogram/liter levels of pesticides such as diazinon, alachlor, and s-metolachlor were detected during the monitoring campaign using both passive and spot sampling whereas higher concentrations were measured by spot sampling in most cases.
  
  
  CONCLUSIONS
  Passive sampling by POCIS provides a useful tool for the monitoring of pesticides in aquatic systems since integrative sampling at rates sufficient for analytical quantitation of ambient levels was observed. Calibration data are in demand for a greater number of compounds in order to extend the use in environmental monitoring.
authors.affiliation: Department of Environmental and Natural Resources Management, University of Ioannina, Agrinio, Greece.
authors.forename: Alphanna-Akrivi
authors.initials: AA
authors.lastname: Thomatou
authors.forename: Ierotheos
authors.initials: I
authors.lastname: Zacharias
authors.forename: Dimitra
authors.initials: D
authors.lastname: Hela
authors.forename: Ioannis
authors.initials: I
authors.lastname: Konstantinou
mesh_terms: D002138:Calibration; D004784:Environmental Monitoring / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006115:Greece; D009930:Organic Chemicals / Q000032:analysis*; D010575:Pesticides / Q000032:analysis*; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D009930:Organic Chemicals; D010575:Pesticides; D014874:Water Pollutants, Chemical